Organisms comprising the oral microbiota contribute to health and disease, and their disruption may indicate, trigger, or influence the course of oral diseases like oral candidiasis. To date, studies of the oral microbiota have primarily focused on bacteria, especially in disease settings.
Organisms residing in the oral cavity (oral microbiota) contribute to health and disease, and influence oral diseases like oral candidiasis (see, e.g., Jenkinson, H. F., et al.; Oral Microbial Communities in Sickness and in Health; Trends Microbiol., Vol. 13, pp. 589 to 95, 2005), an infection caused by the fungus Candida (see, e.g., Nokta, M.; Oral Manifestations Associated with HIV Infection; Curro HIV/AIDS Rep. Vol. 5, pp. 5 to 12, 2008; or Patton, L. L., et al.; Prevalence and Classification of HIV-Associated Oral Lesions; Oral Dis. Vol. 8, pp. 98 to 109, 2002; or Shiboski, C. H.; HIV-Related Oral Disease Epidemiology among Women: Year 2000 Update; Oral Dis. Vol. 8, pp. 44 to 48, 2002), and the most common oral complication of HIV-infection. As has been studied and published, the pathogenesis of oral candidiasis is linked to changes in the CD4+ cell count, antiretroviral therapy (ART), and cigarette smoking in HIV-1-infected patients. Although the introduction of ART has reduced mortality and morbidity as well as the incidence of opportunistic infections including oral candidiasis among HIV-infected patients, recent studies indicate that the decline of oral candidiasis among ART-experienced HIV patients is transient in some HIV-infected individuals. In this regard, a recent study showed that in patients with advanced AIDS, oral yeast colonization was extensive, occurring in 81.1 percent of the 122 patients studied and symptomatic infection occurred in one-third. In addition, resistant yeasts were still common, occurring in 25.3 percent of patients colonized with yeasts or with symptomatic infection. Thus, oral candidiasis remains a significant disease in advanced AIDS, even in the era of ART.
Changes in the human gut microbiota have been associated with conditions like allergies, Celiac's disease, gastric cancer, obesity, anorexia and inflammatory bowel disease. The oral microbiome of the subgingival plaque in HIV-infected patients has also been characterized. However, most studies to date have focused on the bacterial component of the microbiome (bacteriome), in both oral and non-oral body sites with no attention to the mycobiome (fungal members of the oral microbiome). Recently, the oral mycobiome in healthy individuals was characterized using high-throughput multitag pyrosequencing (MTPS), and reported that humans are colonized with up to 85 fungal genera (see, e.g., Ghannoum, M. A., et al.; Characterization of the Oral 25 Fungal Microbiome (Mycobiome) in Healthy Individuals; PLoS Pathogens Vol. 6, e1000713, 2010). Although this study demonstrated the complexity of the human oral microbiome, the specific contribution of the mycobiome to diseases including HIV-infection remained elusive further investigation.